1. Field of the Invention
The present invention broadly relates to ceramic composite bodies having a shape replicated portion thereof and to methods of making the same In particular, the invention relates to ceramic composite bodies comprising a polycrystalline matrix embedding a filler and having a negative pattern shaped by inverse replication of a positive pattern of a parent metal precursor, and to methods of making the composites by infiltrating a bed of filler with the oxidation reaction product of the parent metal precursor, the positive pattern of which is inversely replicated to form the negative pattern of the ceramic composite.
2. Description of Commonly Owned Patent Applications
The subject matter of this application is related to that of copending and Commonly Owned U.S. patent applications Ser. No. 819,397, filed Jan. 17, 1986, which is a continuation-in-part of Ser. No. 697,878, filed Feb. 4, 1985, both in the name of Marc S. Newkirk et al and entitled "Composite Ceramic Articles and Methods of Making Same." These copending applications disclose a novel method for producing a self-supporting ceramic composite by growing an oxidation reaction product from a parent metal into a permeable mass of filler. The resulting composite, however, has no defined or predetermined configuration.
The method of growing a ceramic product by an oxidation reaction is disclosed generically in copending Commonly Owned U.S. patent applications Ser. No. 818,943, filed Jan. 15, 1986 as a continuation-in-part of Ser. No. 776,964, filed Sept. 17, 1985, which is a continuation-in-part of Ser. No. 705,787, filed Feb. 26, 1985, which is a continuation-in-part of Ser. No. 591,392, filed Mar. 16, 1984, all in the name of Marc S. Newkirk et al and entitled "Novel Ceramic Materials and Methods of Making The Same." The employment of an unusual oxidation phenomenon as described in the aforesaid Commonly Owned patent applications, which may be enhanced by the use of an alloyed dopant, affords self-supporting ceramic bodies grown as the oxidation reaction product from a precursor parent metal and a method of making the same. The method was improved upon by the use of external dopants applied to the surface of the precursor parent metal as disclosed in Commonly Owned U.S. applications Ser. No. 822,999, filed Jan. 27, 1986, which is a continuation-in-part of Ser. No. 776,965, filed Sept. 17, 1985, which is a continuation-in-part of Ser. No. 747,788, filed June 25, 1985, which is a continuation-in-part of Ser. No. 632,636, filed July 20, 1984, all in the name of Marc S. Newkirk et al and entitled "Methods of Making Self-Supporting Ceramic Materials".
A method of forming ceramic bodies having one or more shaped cavities therein is disclosed in copending and Commonly Owned U.S. patent application Ser. No. 823,542, filed Jan. 27, 1986 in the name of Marc S. Newkirk et al and entitled "Inverse Shape Replication Method of Making Ceramic Composite Articles and Articles Obtained Thereby" The cavity formed in the ceramic body inversely replicates the shape of a positive pattern or mold of the parent metal which is embedded within and entirely surrounded by a conformable filler which is sufficiently conformable to accommodate differential thermal expansion between the filler and the parent metal plus the melting point volume change of the metal, and which self-bonds at an appropriate temperature to insure that the cavity formed by migration of molten parent metal into the filler (to form oxidation reaction product) does not collapse due to the pressure differential created across the developing cavity wall as a result of the cavity-forming migration.
The entire disclosure of each of the foregoing Commonly Owned Patent Applications is expressly incorporated herein by reference.